Aircraft: CRJ700
Phase of flight: Parked
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy

While returning to the gate due to severe weather and ATC ground stop; the CRJ-700 aircraft was subjected to 2-3 minutes of one and a half inch size hail. The airplane was stopped and the engines were off during the hail; we were waiting for the jetbridge to be moved to the aircraft; and we were on APU power. After the passengers had dis-boarded [de-planed]; I called Dispatch and Maintenance Control to find out if an inspection by a Mechanic was required by company policy. The Maintenance Control person I talked to said I could perform a normal walk around and pay special attention to the top of the fuselage and the top surfaces of the wings; and if no damage was found the rest of the airplane could be deemed undamaged. I performed my inspection; in diffused daylight under a mid-level overcast; of a wet wing and fuselage. I did not see or feel any hail damage. I called Maintenance Control afterward to report my findings; and he said that was all that needed to be done. While passengers were re-boarding; the First Officer and I discussed the situation; and the First Officer suggested I call our regional Chief Pilot to verify there wasn't a company policy requiring a Mechanic's inspection in this situation and that my inspection would be sufficient. My call went straight to the answering machine; and as I needed an immediate answer; I called the Pilot Locator Desk and asked to be connected with any Chief Pilot. The Locator Desk tried to call one or two for me; and then realized all the Chief Pilots were involved in a conference call. He then asked Mr. X personally; if this was an appropriate way to handle the situation; and relayed Mr. X's answer to me that yes; it was. I then continued the flight. After landing and while explaining to the airplane's new crew why we were four hours late; a company Mechanic who had come onboard to check something else overheard me; and seemed surprised that a Preflight Inspection by a pilot would be acceptable after an airplane had been hailed on. He then borrowed a flashlight; looked the plane over and discovered hail dents on the tops of the flaps and spoilers. He showed me what he had seen; and the damage was quite obvious when on dry surfaces and illuminated at a low angle in the dark. After he conferred with Maintenance Control he asked if I would write up the damage; and I did. Two suggestions: 1. A policy requiring a Mechanic's inspection and sign-off after an encounter with hail. 2. Pilots (myself; anyway) should recognize that the preflight and post-flight inspections of the aircraft's general condition [that] we do and are trained to do; are not the same as the more detailed and specific inspections Maintenance people; who have the training and experience to see and recognize subtle damage and are knowledgeable of the conditions to make certain defects apparent; do. 3. Personally I will write-up such events in the future: 'Possible damage from XXXX. Aircraft needs inspection. Severe thunderstorms and lightning shut down departures; so we decided to return to gate to let passengers off aircraft due to lengthy delay and severe weather in the area. We parked at the gate and shut the engines down and while waiting for Gate Agent to bring jetbridge up to airplane; it began to hail. The hail was approx 1' inch; in diameter and light to medium intensity. This lasted approximately three minutes. After the hail stopped and Gate Agent brought up jetbridge; we deplaned the passengers. The Captain and I discussed the policy; or procedure for doing a Hail Event Inspection. The Captain called Dispatch and Maintenance Control to discuss the issue and see what the procedure was and who is able to do it. Maintenance Control told the Captain that an inspection for hail damage could be done by the Captain. The Captain did a walk around and did not find any damage. The outside conditions: light rain; low light due to overcast weather. The Captain called Maintenance Control and reported that he did not see any damage to the aircraft that he noticed. After a delay; we were boarding passengers to return to ZZZ1 and the Captain and I discussed the concern of ours that just doing a walk-around was a good enough inspection. I suggested calling a Chief Pilot to discuss it further.I think that there should be a better policy in place to do a post Hail Event Inspection of the aircraft. This Inspection should be completed and signed-off by a Mechanic who is able to inspect the whole airframe by using ladders/ lifts to see upper fuselage and tail sections. A Captain report's he performed a preflight type walk-around for a hail damage inspection of their CRJ-700 aircraft after Maintenance Control informed him the procedure would be adequate for dispatch. The First Officer suggested calling Chief Pilot who agreed. Mechanic at next station showed Captain the hail dents on flaps and spoilers that were missed.